The invention relates to a turning device operated by compressed air, for example for compressed air tools, having a housing and a rotor, which is rotatably arranged in a front housing part and into whose turbine element the fluid under pressure can flow, having a braking arrangement and a switch for the compressed fluid, which is in operative connection with the braking arrangement and is arranged on a rear housing part in line with a compressed fluid supply conduit.
With such a turning device known from U.S. Pat. No. 5,186,603, the switch constitutes at least partially the rear housing part and can be rotated in a screw thread in relation to the front housing part and a housing cover which receives it. The supply with compressed fluid is opened or closed by means of this rotation. The braking arrangement is spring-loaded and is pressed on the rotor in the course of closing the compressed fluid supply conduit when the switch is turned.
The construction of this known turning device is comparatively elaborate and requires a multitude of components. Moreover, opening and closing the compressed fluid supply conduit cannot be performed with one hand and is therefore impractical and furthermore time-consuming because of the multitude of required revolutions.
It is the object of the present invention to create a turning device of the type mentioned at the outset which requires fewer components and which can be brought to a stop in a simpler and faster way by means of a fluid switch.
This object is achieved by the provision of a sliding switch which encloses the rear housing part in the area of the supply conduit. The sliding switch is provided with axially oriented control pins which are connected and fixed against relative displacement with a brake disk of the braking arrangement.
By means of the steps of the present invention it is achieved that the switch is embodied as a simple sliding switch which cannot only be operated with one hand, but also in a very rapid manner. The direct opening and closing of the braking arrangement by means of the sliding switch is possible because of the slide-proof connection of the brake disk and the sliding switch without requiring further components.
A slide-proof guide for the control pins is achieved by means of a cover of the housing through which the control pins are guided With the provision of vent openings in the housing cover, venting can take place simultaneously with the shut-off and braking of the rotor.
Advantageous embodiments with respect to opening and closing the compressed fluid supply conduit with the aid of the sliding switch ensue due to the supply conduit being interrupted in the rear housing part, with each end of the supply conduit being connected with radial bypass conduits arranged in the rear housing part whose outlet openings can be covered by the sliding switch; due to the sliding switch having an interior annular compressed fluid groove whose width corresponds to the axial distance of the bypass conduits from both ends of the conduit; and due to seal rings being provided in the sliding switch at both sides of the annular groove, the center seal ring of which separates the two bypass conduits.
Further details of the present invention can be taken from the following description, in which the present invention is described in greater detail and explained by means of the exemplary embodiment represented in the drawings.